Nessus is a very well known vulnerability scanner used by many large and small companies to assess their systems and correct the issues found in them. Cybersecurity teams and specially auditors, make heavy use of tools like this in order to follow up the state of infrastructure and environments. Having a tool like this saves […]

Nessus vulnerability scanner

A brief introduction to Regular Expressions
A regular expression is a set of characters, a string of characters if you will, that specify a pattern. Ever used the grep command? It makes use of them. The ‘grep’ command is very handful when one needs to look for certain things inside a text file, or looking for some specific pattern from another […]

How to install Redis for WordPress on FreeBSD
I happen to self-host a few WordPress sites on FreeBSD. And as much as one can configure OP-Cache to improve PHP’s performance, object cache is a must for many WordPress sites. This how to install Redis for WordPress on FreeBSD will explain how to install an object cache (Redis) for WordPress (via plugin) on this […]

What is UNIX?
UNIX is an operating system. And your known equivalent is Windows or the Mac. You may even know about Linux. The purpose of an OS is to accommodate programs in order to get some work done. Editing pictures, browsing the web or serving data from a database. It is the thing that lets you operate […]

How to format an USB drive on FreeBSD
File system support on FreeBSD falls onto UFS (UNIX File System) or originally named the FFS (Fast File System and on ZFS (Zetabyte File System). If you are using your box as a desktop-workstation you will use USB drives to share files with other systems, to carry things on your pocket or safe the day […]

How to install ModSecurity 3 on FreeBSD
A couple of years ago I wrote a guide on how to install Modsecurity on FreeBSD. Now the program is on its third iteration so a new article is needed. Or so I think. In this article I’ll be covering Modsecurity 3 applied to protect Apache HTTP. If you find the articles in Adminbyaccident.com useful […]

How to configure a Virtual Host in Apache
You may have just one website and that is ok. If that is your case you can avoid this entire chapter. But some of you may also have several websites. And quite probably you want to use one single public ip to resolve all the domains you have. The Apache documentation is the main resource […]

A word on Spectre and Meltdown
As professionals and many aficionados know, early this year some widespread vulnerabilities were found on Intel CPU’s as well as on AMD’s. It was a bit later discovered the flaws also affected some RISC architectures such as Power and ARM. Everybody went nuts and the world seemed to be tumbling because of two CPU vulnerabilities […]

How to configure FreeBSD to use a webcam (version 12 and 13)
Introduction. Unlike many Linux distributions the FreeBSD operating system comes quite crude out of the box. What others will interpret as a disadvantage, with some knowledge on the system, others see the power to serve. Anyone willing to have a nice FreeBSD desktop experience with little effort, there are a couple of BSD-based distributions, like […]

How to load and unload kernel modules in Linux
Kernel modules permit enabling hardware features on a given system. For example, if we need to read from a particular filesystem from a hard drive, we need to load a particular kernel module. Or use a specific network card, a sound card or sound device, a video display, etc. This is mostly done automatically in […]
